Latest Headlines

DEFORMATION MONITORING SYSTEM FOR NEW YORK SUBWAY CONSTRUCTION PROJECT USES SURVEYING TECHNOLOGY FROM LEICA GEOSYSTEMS

October 12, 2006
/ Print / Reprints /
ShareMore
/ Text Size+
(Norcross, Ga., 4 October 2006) Workers on a major underground construction project in New York City are depending on high-precision surveying instruments from Leica Geosystems to ensure the safety of personnel and structures as part of an automated deformation monitoring system.

The $400 million South Ferry Terminal improvement program involves a major upgrade of the existing station, which is located underneath Peter Minuit Plaza in Lower Manhattan, adjacent to Battery Park and the Staten Island Ferry Terminal. The work is being done under a design-build contract by Schiavone Construction Company of New Jersey, and includes underpinning of the existing tunnels using mini-piles and cut-and-cover excavation of a new tunnel. Schiavone contracted with Mueser Rutledge Consulting Engineers (MRCE) and Geocomp Corporation to provide specialty geotechnical design and monitoring services for the underpinning and tunnel construction.

The monitoring system developed by Geocomp and MRCE includes 10 Leica TCRP1201 total stations, monitoring more than 450 prisms above and below ground. The system also includes seismographs inside the tunnels to record vibrations, tiltmeters on selected structures to monitor deflection, and inclinometers installed in the support-of-excavation walls and in the ground in front of nearby historic structures to monitor lateral deflections.

The Leica TCRP1201 robotic total stations, permanently mounted at fixed locations, take continuous laser measurements to prisms mounted on buildings and other structures on the surface within a several-block radius of the worksite. Other TCRP1201 total stations are performing the same function underground, taking precise measurements to prisms attached to the tunnel walls. The automatic monitoring system alerts authorities to any out-of-tolerance movements that could pose a danger to the buildings or workers above and below ground. All 10 total stations are controlled and synchronized using Leica GeoMoS monitoring software.

"The monitoring regime developed for this project focuses on the existing tunnels and nearby structures, including some very important historic buildings and facilities within Battery Park," said W. Allen Marr, CEO of Geocomp. "The project presented unique challenges for monitoring implementation and logistics. The existing tunnels are being kept in operation during the construction, which limits access to the tunnels to once every few weeks. Movement tolerances are fractions of an inch. These conditions demanded we use the most reliable, rugged and repeatable measuring systems."

Because of the limited access to the monitored locations, Geocomp deployed a wireless monitoring system for remote access and automated data transfer to a Web-based monitoring and reporting system. Data is available 24/7 via a secure real-time Internet link using Geocomp's iSiteCentralÔ system.

"Precise deformation monitoring is increasingly becoming a standard requirement for major engineering projects, especially those involving underground excavations, to protect nearby structures from damage during the construction process," said Gerard Manley, vice president of engineered solutions for Leica Geosystems. "More importantly, it provides a critical margin of safety for workers on the job, as well as people going about their daily business in the vicinity of the excavation. We are very pleased that we can play a role in being a good neighbor to the members of the community affected by the construction project."

Leica Geosystems - when it has to be right

With close to 200 years of pioneering solutions to measure the world, Leica Geosystems products and services are trusted by professionals worldwide to help them capture, analyze, and present spatial information. Leica Geosystems is best known for its broad array of products that capture accurately, model quickly, analyze easily, and visualize and present spatial information.

Those who use Leica products every day trust them for their dependability, the value they deliver, and the superior customer support. Based in Heerbrugg, Switzerland, Leica Geosystems is a global company with tens of thousands of customers supported by more than 2,400 employees in 22 countries and hundreds of partners located in more than 120 countries around the world. Leica Geosystems is part of the Hexagon Group, Sweden.

Did you enjoy this article? Click here to subscribe to POB

You must login or register in order to post a comment.

Multimedia

Videos

Image Galleries

HxGN Live

More than 3,500 attendees from more than 70 countries attended HxGN Live, the annual Hexagon AB user conference, at the MGM Grand Hotel & Casino in Las Vegas on June 3-6. About 450 keynotes and panel discussions were held, and several companies from around the world exhibited their geospatial products. Here are a few snapshots from the event.

9/30/14 2:00 pm EDT

Technical Workflows on the Job Site Using 3D Laser Scanning

The purpose of this webinar is to dig into different laser scanning workflows and techniques.

POB

POB September 2014

2014 September

In this September 2014 issue of POB, we take a look at a book that reveals how a rare-map dealer made millions stealing ancient maps. Also, discover the secrets of a 21st-century surveyor and how technology enables small surveying businesses to ease growing pains and maximize their potential.

Table Of Contents Subscribe

Surveying Career

Would you recommend surveying as a career to a current college student?
View Results Poll Archive

Point of Beginning Store

M:\General Shared\__AEC Store Katie Z\AEC Store\Images\POB\epubsite\Statues-pic-large.gif
Surveyor Statues

The perfect gift or award for any special occasion.

More Products

Clear Seas Research

Clear Seas ResearchWith access to over one million professionals and more than 60 industry-specific publications, Clear Seas Research offers relevant insights from those who know your industry best. Let us customize a market research solution that exceeds your marketing goals.

Geo Locator

Buyers Guide

The #1 buyers' guide for land surveyors and geomatics professionals. Search listings for software and equipment manufacturers, equipment dealers and professional services. CLICK HERE to view GeoLocator.

STAY CONNECTED

Facebook logo Twitter logo  LinkedIn logo  YouTube logoRPLS small logo

Google +